"Jere Lull" wrote in message
...
In article ,
Neon John wrote:

Even Roland's appreciation of the "big picture" is incorrect. Modern
supercritcal fossil plants achieve overall efficiencies in the 50%
range.
Even the good old nuke are in the high 30s. The Sequoyah Nuclear Plant
where
I worked for about 10 years recently replaced the steam generators. The
improved design plus some plant upgrades pushed the efficiency to 38%
and a
fraction, something that spawned a small staff party. Oh, and BTW,
Roland,
the waste heat goes up the cooling tower stacks and not into the lake,
at
least not to any significant extent. Much to the chagrin of local
fishermen
who discovered that the warm water (pre-cooling towers) spawned great
fish
growth and fishing conditions.
John De Armond

Depending on *how* it's measured, efficiency can be higher. Back in '70,
I worked as a co-op at the Eddystone plant (Philly area), then arguably
the most efficient plant in the world -- only the USSR supposedly had a
better one. Steam started at 4,999.5 psi according the gauge, ended in
partial vacuum. They burned (actually closer to exploded) 1-200 tons of
coal an hour and we STILL needed heaters in the "basement" labs in the
winter. [yes, we had walls ;-)] They only used the gas turbines (jet
engines) in the yard when absolutely necessary, because their efficiency
was so low.

By each measure, efficiency was pretty high.

But are they making plants like that any more? When they built units 3 &
4, they went back to a "mere" 1-2000 psi. AFAIK, only one supercritical
production nuke was built: Peachbottom.

Indian Point I (long shutdown now) was a nuke that used the reactor to make
saturated steam, then used an oil-fired superheater to superheat the steam.
Not sure how hot it ran, but pressure was only about 1000 psi (due to the
limits of the nuke's steam-generator).

In recent past, the industry has been going for combined-cycle gas-turbine.
Less pollution controls needed and overall cycle efficiencies running close
to 60%. But this has raised demand on natural gas, so that price has
started to climb and things are shifting once again.

daestrom

"Jere Lull" wrote in message
...
In article ,
Neon John wrote:

Even Roland's appreciation of the "big picture" is incorrect. Modern
supercritcal fossil plants achieve overall efficiencies in the 50%
range.
Even the good old nuke are in the high 30s. The Sequoyah Nuclear Plant
where
I worked for about 10 years recently replaced the steam generators. The
improved design plus some plant upgrades pushed the efficiency to 38%
and a
fraction, something that spawned a small staff party. Oh, and BTW,
Roland,
the waste heat goes up the cooling tower stacks and not into the lake,
at
least not to any significant extent. Much to the chagrin of local
fishermen
who discovered that the warm water (pre-cooling towers) spawned great
fish
growth and fishing conditions.
John De Armond

Depending on *how* it's measured, efficiency can be higher. Back in '70,
I worked as a co-op at the Eddystone plant (Philly area), then arguably
the most efficient plant in the world -- only the USSR supposedly had a
better one. Steam started at 4,999.5 psi according the gauge, ended in
partial vacuum. They burned (actually closer to exploded) 1-200 tons of
coal an hour and we STILL needed heaters in the "basement" labs in the
winter. [yes, we had walls ;-)] They only used the gas turbines (jet
engines) in the yard when absolutely necessary, because their efficiency
was so low.

By each measure, efficiency was pretty high.

But are they making plants like that any more? When they built units 3 &
4, they went back to a "mere" 1-2000 psi. AFAIK, only one supercritical
production nuke was built: Peachbottom.

Indian Point I (long shutdown now) was a nuke that used the reactor to make
saturated steam, then used an oil-fired superheater to superheat the steam.
Not sure how hot it ran, but pressure was only about 1000 psi (due to the
limits of the nuke's steam-generator).

In recent past, the industry has been going for combined-cycle gas-turbine.
Less pollution controls needed and overall cycle efficiencies running close
to 60%. But this has raised demand on natural gas, so that price has
started to climb and things are shifting once again.

daestrom

On 31-Mar-2004, Neon John wrote:

Just ignore Roland. He just likes to hear himself type and throw out fancy
terms. Doesn't have a clue. Your measurements were right on target. Even
the temperature selected. The water heater I recently installed in one of my
cabins came from the Home Depot with the 'stats set at 115 deg F. Probably
the lawyers at work again. I bet just about nobody changes that setting.

Even Roland's appreciation of the "big picture" is incorrect.

Yes, Roland's "big picture" is incorrect. The problem with European
environmentalists like him is that they are cultural imperialists: They want to
impose their standard of living, cars, energy generation, insulation, house
sizes, lighting and room temperatures on all other cultures. They even have
standards for family size. I could care less whether he rides a bicycle or
drives a Mercedes, but it really bothers him that I drive a SUV and have 200
watts of light in my office. But what's worse is that if he had the
opportunity, he would impose his political/environmental/social policy on the
whole world. "Liberals" are only tolerant of other liberals; they are dogmatic
and unwilling to accept those who prefer different lifestyles.

In article ,
Neon John wrote:

Even Roland's appreciation of the "big picture" is incorrect. Modern
supercritcal fossil plants achieve overall efficiencies in the 50% range.
Even the good old nuke are in the high 30s. The Sequoyah Nuclear Plant where
I worked for about 10 years recently replaced the steam generators. The
improved design plus some plant upgrades pushed the efficiency to 38% and a
fraction, something that spawned a small staff party. Oh, and BTW, Roland,
the waste heat goes up the cooling tower stacks and not into the lake, at
least not to any significant extent. Much to the chagrin of local fishermen
who discovered that the warm water (pre-cooling towers) spawned great fish
growth and fishing conditions.
John De Armond

Depending on *how* it's measured, efficiency can be higher. Back in '70,
I worked as a co-op at the Eddystone plant (Philly area), then arguably
the most efficient plant in the world -- only the USSR supposedly had a
better one. Steam started at 4,999.5 psi according the gauge, ended in
partial vacuum. They burned (actually closer to exploded) 1-200 tons of
coal an hour and we STILL needed heaters in the "basement" labs in the
winter. [yes, we had walls ;-)] They only used the gas turbines (jet
engines) in the yard when absolutely necessary, because their efficiency
was so low.

By each measure, efficiency was pretty high.

But are they making plants like that any more? When they built units 3 &
4, they went back to a "mere" 1-2000 psi. AFAIK, only one supercritical
production nuke was built: Peachbottom.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/

On Thu, 1 Apr 2004 01:04:20 GMT, "Phil Sherrod"
wrote:


The main issue with electric water heaters, as far as I'm concerned, is that
the Carnot-limited power source wastes at least 60% of the fuel source heat
to the local rivers and dams, for you to take the (optimistic) 40% and
convert it back to heat.

I have absolutely no control over that nor was my study directed at that issue.

Your case study is flawed, and you lack appreciation of the big picture.

I never claimed to be presenting either a study or a solution to the "big
picture" of energy usage. My study was simply to measure the actual heat loss
energy for one water heater in a known environment. As shown above, you can
adapt the figures to other situations.

Phil,

Just ignore Roland. He just likes to hear himself type and throw out fancy
terms. Doesn't have a clue. Your measurements were right on target. Even
the temperature selected. The water heater I recently installed in one of my
cabins came from the Home Depot with the 'stats set at 115 deg F. Probably
the lawyers at work again. I bet just about nobody changes that setting.

Even Roland's appreciation of the "big picture" is incorrect. Modern
supercritcal fossil plants achieve overall efficiencies in the 50% range.
Even the good old nuke are in the high 30s. The Sequoyah Nuclear Plant where
I worked for about 10 years recently replaced the steam generators. The
improved design plus some plant upgrades pushed the efficiency to 38% and a
fraction, something that spawned a small staff party. Oh, and BTW, Roland,
the waste heat goes up the cooling tower stacks and not into the lake, at
least not to any significant extent. Much to the chagrin of local fishermen
who discovered that the warm water (pre-cooling towers) spawned great fish
growth and fishing conditions.

John



---
John De Armond

http://bellsouthpwp.net/j/o/johngd/
Cleveland, Occupied TN

On 31-Mar-2004, "Roland Paterson-Jones" wrote:

Mmm, hot water delivered is 114F, that's 45C, hardly luke-warm!

We have to take the rest of the measurements with a pinch of salt then.

As you know, heat loss is proportional to the temperature delta. How about a
realistic scenario.

OK, let's bump the temperature up to 125F. That's a temperature differential
of 64F.

That means the heat loss and cost increases by a factor of 64/51.

The average heat loss cost at 114F is $4/month, so at 125F it will be $5.02.
(4*64/51)

But, of course, don't forget that many people keep their water heaters in areas
that are warmer than 61F, so the temperature differential may be lower than
mine.

The main issue with electric water heaters, as far as I'm concerned, is that
the Carnot-limited power source wastes at least 60% of the fuel source heat
to the local rivers and dams, for you to take the (optimistic) 40% and
convert it back to heat.

I have absolutely no control over that nor was my study directed at that issue.

Your case study is flawed, and you lack appreciation of the big picture.

I never claimed to be presenting either a study or a solution to the "big
picture" of energy usage. My study was simply to measure the actual heat loss
energy for one water heater in a known environment. As shown above, you can
adapt the figures to other situations.

The EPA average national power rate is 8 cents per KWH. So, using the EPA
power rate, the cost of keeping the idle water heater hot is 13.35 cents/day or
$4.00/month or $48.73/year.


Phil, Thanks for the complete info.

I'm MORE than willing to pay $49/yr so I can have hot water when I
turn the handle.

The losses must be a bit larger with a 6 gal RV water heater but it is
sure nice to have hot water!

Based on your data it'd probably take quite a while to recover the
cost of an "instantaneous" heater. I'll wait 'til my old fashioned
one fails before looking at greater efficiency.

I recently did some cold weather camping & was surpised at how little
I missed the hot water. I guess the new detergents are much better
than soap for getting things clean with cold water.

Thanks again and please continue to report useful data. Ignore those
who turn every posting into some kind of ideological argument (they
are ideots!)

The EPA average national power rate is 8 cents per KWH. So, using the EPA
power rate, the cost of keeping the idle water heater hot is 13.35 cents/day or
$4.00/month or $48.73/year.


Phil, Thanks for the complete info.

I'm MORE than willing to pay $49/yr so I can have hot water when I
turn the handle.

The losses must be a bit larger with a 6 gal RV water heater but it is
sure nice to have hot water!

Based on your data it'd probably take quite a while to recover the
cost of an "instantaneous" heater. I'll wait 'til my old fashioned
one fails before looking at greater efficiency.

I recently did some cold weather camping & was surpised at how little
I missed the hot water. I guess the new detergents are much better
than soap for getting things clean with cold water.

Thanks again and please continue to report useful data. Ignore those
who turn every posting into some kind of ideological argument (they
are ideots!)